Barack Obama has appeared on the popular late-night satirical news show of comedian Jon Stewart as the US President looked to spark enthusiasm among younger voters ahead of Tuesday's congressional election.
The appearance comes three days before Stewart holds a "Rally to Restore Sanity" - a denunciation of political extremism, likely to draw tens of thousands of fans to the US capital.
It would be the kind of huge crowd that Mr Obama often drew during his campaign for president. However,such turnouts have become rare for the president and his fellow Democrats - Republicans have strong prospects for winning control of the House of Representatives and a slight chance of winning the Senate.
Mr Obama has been trying to shrink what political analysts call the "enthusiasm gap", trying to motivate key elements of his base, such as union workers, African-Americans, Hispanics and - with his Stewart appearance - younger voters.
Interviewed on The Daily Show with Jon Stewart, which is extremely popular with young viewers, the President lauded several members of Congress for taking votes he said they knew would be bad politically but who did so because it was the right thing to do.
"My hope is that those people are rewarded for taking those tough votes," Mr Obama said. If so, "then Democrats will be rewarded on election night."
Mr Obama named Representative Tom Perriello - the Virginia Democrat voted for the President's historic health care bill and is in a tight race. The President plans to be in Virginia on Friday to campaign with Mr Perriello.
This year's election will decide contests for all 435 seats in the House, 37 places in the 100-member Senate and 37 state governorships.
With a takeover in the House expected, Republicans also are forecast to make significant gains in the Senate but fall short of capturing a 51 seat majority. Their prospects are even better in the governor's races.
With the 50 states preparing to draw new congressional district maps after this year's national census, Republican governors will have a major say in that process - one that would strongly favour Republican candidates in 2012.